Field of the Invention
The present invention relates to an automatic transmission for a vehicle. More particularly, the present invention relates to a planetary gear train of an automatic transmission for a vehicle of improving power delivery performance and fuel efficiency by achieving ten forward speed stages using a driving point positioned at a low engine speed.
Description of Related Art
Recent increases in oil prices are triggering stiff competition in enhancing fuel consumption of a vehicle.
In this sense, research is being conducted on engines in terms of reducing weight and improving fuel efficiency by down-sizing, and research is also being conducted to ensure both drivability and competitiveness by maximizing fuel efficiency by implementing an automatic transmission with multiple speed-stages.
However, in the automatic transmission, as the number of speed stages increase, the number of internal components (particularly, planetary gear sets) increase, which may deteriorate installability and/or power flow efficiency and may increase production cost, and weight.
Therefore, in order to increase an effect of improving fuel efficiency by implementing an automatic transmission with multiple speed-stages, it is important to develop a planetary gear train capable of maximizing efficiency using a small number of components.
In this respect, an eight-speed automatic transmission has been recently introduced, and a planetary gear train for an automatic transmission enabling more shift stages is under investigation.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.